# UN Volumetric Swelling Eigenstrain

Calculates the change in volume due to swelling in UN fuel. This class applies a volumetric strain correction before adding the strain from this class to the diagonal entries of the eigenstrain tensor.

## Description

This class, UNVolumetricSwellingEigenstrain, calculates the volumetric swelling of UN fuel. An empirical expression for the swelling of UN was determined using data from S. Ross (1989) as (1) where is the instantaneous burnup, the temperature in Kelvin, and the initial density as a percent of theoretical. The volumetric swelling is calculated by integrating the incremental strain over burnup.

## Example Input Syntax


[./swelling]
type = UNVolumetricSwellingEigenstrain
temperature = temp
burnup = burnup
density_percent = 95
eigenstrain_name = swelling
[../]
(test/tests/tensor_mechanics/u3si2un_eigenstrains/un_swelling.i)

[./swelling]
type = VSwellingUN
block = '1 2 3 4 5 6 7'
temp = temp
burnup = burnup
[../]
(test/tests/un_swelling/VSwellingUN.i)

## Input Parameters

• density_percentThe initial theoretical density (percent).

C++ Type:double

Description:The initial theoretical density (percent).

• temperatureCoupled temperature in Kelvin

C++ Type:std::vector

Description:Coupled temperature in Kelvin

• burnupCoupled Burnup variable in FIMA

C++ Type:std::vector

Description:Coupled Burnup variable in FIMA

• eigenstrain_nameMaterial property name for the eigenstrain tensor computed by this model. IMPORTANT: The name of this property must also be provided to the strain calculator.

C++ Type:std::string

Description:Material property name for the eigenstrain tensor computed by this model. IMPORTANT: The name of this property must also be provided to the strain calculator.

### Required Parameters

• computeTrueWhen false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

Default:True

C++ Type:bool

Description:When false, MOOSE will not call compute methods on this material. The user must call computeProperties() after retrieving the Material via MaterialPropertyInterface::getMaterial(). Non-computed Materials are not sorted for dependencies.

• base_nameOptional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

C++ Type:std::string

Description:Optional parameter that allows the user to define multiple mechanics material systems on the same block, i.e. for multiple phases

• save_swellingFalseShould the swelling be saved in a material property

Default:False

C++ Type:bool

Description:Should the swelling be saved in a material property

• boundaryThe list of boundary IDs from the mesh where this boundary condition applies

C++ Type:std::vector

Description:The list of boundary IDs from the mesh where this boundary condition applies

• blockThe list of block ids (SubdomainID) that this object will be applied

C++ Type:std::vector

Description:The list of block ids (SubdomainID) that this object will be applied

### Optional Parameters

• enableTrueSet the enabled status of the MooseObject.

Default:True

C++ Type:bool

Description:Set the enabled status of the MooseObject.

• use_displaced_meshFalseWhether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

Default:False

C++ Type:bool

Description:Whether or not this object should use the displaced mesh for computation. Note that in the case this is true but no displacements are provided in the Mesh block the undisplaced mesh will still be used.

• control_tagsAdds user-defined labels for accessing object parameters via control logic.

C++ Type:std::vector

Description:Adds user-defined labels for accessing object parameters via control logic.

• seed0The seed for the master random number generator

Default:0

C++ Type:unsigned int

Description:The seed for the master random number generator

• implicitTrueDetermines whether this object is calculated using an implicit or explicit form

Default:True

C++ Type:bool

Description:Determines whether this object is calculated using an implicit or explicit form

• constant_onNONEWhen ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

Default:NONE

C++ Type:MooseEnum

Description:When ELEMENT, MOOSE will only call computeQpProperties() for the 0th quadrature point, and then copy that value to the other qps.When SUBDOMAIN, MOOSE will only call computeSubdomainProperties() for the 0th quadrature point, and then copy that value to the other qps. Evaluations on element qps will be skipped

• output_propertiesList of material properties, from this material, to output (outputs must also be defined to an output type)

C++ Type:std::vector

Description:List of material properties, from this material, to output (outputs must also be defined to an output type)

• outputsnone Vector of output names were you would like to restrict the output of variables(s) associated with this object

Default:none

C++ Type:std::vector

Description:Vector of output names were you would like to restrict the output of variables(s) associated with this object

### Outputs Parameters

• total_swelling_scaling_factor1Scaling factor to be applied to the swelling strain. Used for sensitivity and calibration studies

Default:1

C++ Type:double

Description:Scaling factor to be applied to the swelling strain. Used for sensitivity and calibration studies